The use of surveillance systems to record cash transactions for later review are well known in the art. For example, U.S. Pat. No. 4,337,482--Coutta, discloses a surveillance system that monitors and records transactions that occur at a number of cashier lanes. In Coutta, a single television camera, mounted on a rail, can be positioned to make a video recording of the transactions that occur at a single selected cashier lane. At column 4, lines 25-42, Coutta discloses that the digital transaction data from the cash register in the selected cashier lane is fed into a video character generator to provide a composite video picture, illustrated in FIG. 6, in which an alpha-numeric description of the transaction data overlays the video image of the transaction. When, as provided in Coutta, a composite video image is generated with alpha-numeric information relating only to a single cashier lane, it is usually possible to position the camera so that the alpha-numeric overlay does not obscure a useful portion of the recorded video image. However, if a single camera is used to record simultaneously the transactions that occur at a plurality of cashier lanes, it is likely that the alpha-numeric overlay data will obscure an important part of the video image of at least one of the transaction lanes. This likelihood is further increased when a large number of parameters are displayed simultaneously for all of the cashier lanes.
U.S. Pat. No. 4,630,110--Cotton, et al., discloses a surveillance system which monitors and records the signals from a number of video cameras. In the example illustrated in FIG. 3A of Cotton, et al, the video images from 4 cameras are combined, two of the cameras being focused on cash registers. Beginning at column 8, line 65, Cotton et al. discloses that textual information can be displayed at the lower portion of the combined display and that certain prior art systems used the audio track of a video cassette recorder to store the data to be displayed.
Another prior art surveillance system, as disclosed in U.S. Pat. No. 4,145,715--Clever, generates two levels of surveillance recordings. The first level, generated by tape recorder 42, contains a record of all transactions while the second level, generated on tape recorder 54 contains only selected transactions. As stated at column 4, lines 18-22, transaction data such as price and department number go to a character generator 32, and, as stated at column 3, lines 45-68, and at column 5, lines 17-28, the character generator output is mixed with the video image to create a composite video frame recorded by the video tape recorder (VTR) 42. This composite video frame consists of alpha-numeric transaction data which overlays the transaction video image. The Clever patent also discloses at column 4, lines 28-32 and at column 5, lines 21-23, that digital information is stored in the leader 50 of each frame. Beginning at column 8, line 67, Clever describes a system in which a single camera scans several point-of-sale stations. Although Clever discloses that a single camera can be used to scan several point-of-sale stations, Clever records a video image that contains alpha-numeric transaction data that overlays the video transaction image. This overlay can degrade the clarity of the resultant video transaction image. As the devices that read the bar codes on the articles being sold become more sophisticated, more alpha-numeric characters describing the transaction are generated for display which further tends to clutter and obscure the composite video image. As the number of lanes being recorded increases, it becomes more difficult to overlay all of the alpha-numeric transaction data at positions that will not obscure an important part of the video transaction image. The clarity of the video image of a transaction is particularly important when the transaction lanes are outdoors and are recorded under varying light and weather conditions.
The prior art surveillance recording systems make continuous video recordings of the transactions. If a typical transaction takes 3 minutes and 30 frames are recorded each second this results in 5400 frames being recorded for that transaction. I have found in many situations, such as for supermarket transactions, a quick check of the validity of the transaction can be obtained from a single video frame. Namely, a picture of the merchandise that is the subject of the transaction is viewed at the start of the transaction along with a summary, such as the cost of the goods totaled at the end of the transaction. It is believed that one transaction can be summarized in a single or perhaps 3 or 4 video frames thereby reducing the recording volume by a factor in the range of 1350 to 5400.
It is, therefore, one object of this invention to provide a surveillance recording system in which either single or multiple cameras simultaneously record transactions that occur at a plurality of lanes for recording as a frame of video on a single volume of a recording medium.
It is another object of this invention to record on the recording medium all of the status and transaction data associated with the video image of a transaction in a manner that preserves the clarity of the video image of the transaction.
Another object of this invention is to provide a surveillance recording system that records outdoor transactions and provides an alpha-numeric display of transaction data during playback.
Another object of this invention is to provide a surveillance recording system of transactions occurring in a plurality of cashier lanes in which, during the playback mode, the alpha-numeric status and transaction data associated with a selected cashier lane can be selectively positioned so as to generate a composite overlay video image in which the clarity of the video image at the selected cashier lane is not degraded.
And yet another object of the invention is to provide a system for making a snapshot summary video frame of a transaction consisting of a video frame of the goods at a cashier lane at the beginning of a transaction with an alpha-numeric summary overlay generated at the completion of the transaction.